The aim of this project is to uncover, assess and contrast mechanisms that are responsible for impairments in cognitive functioning in different forms of neuropsychiatric disorders, emphasizing syndromes that are associated with alcohol abuse. A cognitive neuroscience prospective along with brain imaging and neuropharmacological methods are used to consider how disordered cognitive functioning in alcoholics is involved in the development and maintenance of alcohol addiction and abuse. Reaseach studies have been designed to test a set of hypothesis that there are selective impairments in reflective cognitive operations (in contrast to data, or stimulus-driven cognitive operations), particularly as expressed in problems in inhibition in memory, learning, planning as in decision processes, and attention in detoxified alcoholics. The goals of these studies is to assess and evaluate whether; a) these deficit are independent of other aspects of impaired cognitive functioning in these patients; b) the neurobiological and behavioral mechanisms of impairments in reflective cognitive operations; and c) whether these deficit are relatively unique to alcholics, i.e, are not observed in patients with other forms of neuropsychiatric disorders; d) conditions that potentiate and attenuate underlying impairments in reflective- inhibitory cognitive functions; e) clinical and therapeutic implications of this type of cognitive impairment and f) impairments in cognition that may be antecedents to the development of alcoholism. We have found that alcoholics demonstrate highly selective impairments in their ability to plan strategically in learning and remembering and these subjects are impairments in inhibition such as; 1) errors in remembering; 2) inability to disengage from irrelevant information in attention (using a new method for exploring different forms of inhibition in attention, i.e., the "attentional blink"); 3) inability to track the source of what is remembered; 4) and tend to be stimulus-driven rather than conceptually-driven in many perception, learning and remembering. All of these deficits appear in patients that are unimpaired in most other facets of cognitive functioning. The specific deficits in cognitive functioning apparent in detoxified alcoholics are apparent in both type I and type II alcoholics and are independent of total lifetime consumption of alcohol. The specific deficits in cognitive functioning stand in sharp contrast to the impairments noted in patients with other forms of neuropsychiatric disorder (such as unmedicated depressed patients) as well as normal aging. For example the impairments in normal aging are generalize across virtually all cognitive domains. In depressed patients there is no evidence of an impairment in reflective functions or in inhibition. Instead depressed patients express a selective deficit in implicit learning and memory while explicit memory, perception, access to semantic and other forms of knowledge, and other cognitive functions are spared.